Is anyone out there putting together a key chain sized 100lm or more light? I am thinking about creating such a monster while learning a CNC machine. I think it would utilize a Cree XR-E Q5, 700ma driver 5 mode, and about 150mah 3.7v battery. It will have USB charging and around a 10 minute runtime a max power and 40 minutes on low. End size goal is 46mm x 19mm x 10mm smaller than most usb thumb drives. It will be a great EDC and can be charged almost anywhere now a days. Just playing with the idea.
Key Chain Sized 100lm+ light?
- Thread starter magudaman
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Wiseguyzz_Inc_
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Sounds like a pretty impressive project! Please post some pics if/when you get it constructed.... Sure would beat my current keychain light, the Streamlight Nano ands its whopping 10 lumens 
tolkaze
Enlightened
Could you use a capacitor for the power storage instead of a battery? because at that current draw, you would be putting the cell under about 4.5C discharge, which would be bad
sol-leks
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There are a number of lights out there that live up to this but I guess they are mostly cr2 lights which are usually custom. Except for the quark mini cr2.
I edc a quark mini 123 on my keychain but alot of ppl wouldnt really consider it key chain sized.
I edc a quark mini 123 on my keychain but alot of ppl wouldnt really consider it key chain sized.
What I think is wrong with that is they are way to fat! I think of a small key chain light as a AAA light, AA might even be pushing it for me on my key chain. Thats why a key chain light ends up being a backup to whatever other flashlight I decide to carry that day.
Well the batteries I am looking at are rated at 15c or 2.25amps continuous. They stem from the radio controlled market and used running ultra light planes and helicopters. Capacitors would work great if they actually held a lot more power. The current cell holds around .5 watt hours of power. A capacitor of say 12v 1 farad which is about 6inches long 4in diameter has all of .04 watt hours available, not enough to run the light for more than a couple seconds. Capacitor are good for filtering power and providing extremely short burst of power.
Letomax
Newly Enlightened
Sounds like a great idea! Especially being able to charge via USB...
Seems like thats the trend now days, ITP has the R01 rechargeable, and there are some chargers that charge via USB, it only makes sense since USB is so popular now. The only thing is in about 1 or 2 years USB 3.0 will be the replacement, which will hopefully bring more advanced and powerful USB chargers and Flashlights! :thumbsup:
AnAppleSnail
Flashlight Enthusiast
I've been scheming this too just this week. I was looking at a way-underdriven XR-E because I have them laying around... the charge circuit may be beyond my ability to make, though.
Edit:
http://www.instructables.com/id/USB-Li-ion-battery-charger/
Hmm, maybe not.
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HorseFilms
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I'd love to see what you've come up with, sir.
Gregozedobe
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(I like small and bright)
(I like small and bright)Starchaser
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Qmotion SIS
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I'm actually looking for the most powerful backup pocket light that takes a single CR123A battery. I know nothing of buildng flashlights.
Well I need to order some parts so, it will probably be a while before I update again, I need to make sure this thing will work electronics wise before I go much further. But here is a design to fit all the currently spec'd electronics. Would run the LED at around 165 lumens according the Data sheets. End size is 57mm x 22mm x 14mm, little bit bigger than I wanted.
Gregozedobe
Enlightened
At that size/volume you will be up against some AAA and CR2 lights (and some of the compact 123 based lights). However, here on CPF all you seem to need to sell new lights are some desirable features that are hard to find in other lights - maybe having high CRI LEDS, user programmable with very low moonlight levels and hidden strobes/beacons/SOS functions will make it viable.
Good luck :thumbsup:
AnAppleSnail
Flashlight Enthusiast
User programmable by USB? IE a text file like so:
memory=true
memset=1
doubleclick to change = true
presshold to change = false
presshold for hidden = true
cycle for hidden = false
set_1 0000
set_2 1
set_3 10
set_4 100
set_5 1000
set_6 1536
hid_5 Strobe
hid_6 SOS
hid_3 findme
Set to remember modes used for more than 1 second. This will be the mode at next power-on. Setting 1 is 1/1024 mA (I dunno, something to set the number, 000 for 'super low'), and so on. Hidden modes are reached with a press and hold. Mode is changed with a double click
This might ask more of a microcontroller than can be given, remembering several variables and what to do with them.
I think CR123 are out as to carrying on your key ring, and my only CR2 light has a huge reflector and would definitely be out. My Arc and other AAA lights are only running 10 lumens and I hope this new unit at 750ma across the LED will be pumping out 150 lumens. Programmable modes would be awesome! I like AnAppleSnail idea in the programming!
The thumb drive represents the flashlight and has surprisingly close dimensions:
AnAppleSnail,
I love that idea! I actually have a little pen video camera that has you program the date and time in a similar fashion to that. I think the light could actually be reduced in size if I could combine the charger, driver, BMS in one very smart board. Currently I would be using off the shelve parts but maybe someday I could implement that. Great now I gotta add my electrical engineering degree to the list of todo.
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